Subject: Re: compression?
Author: Giller,Bruce C.
Date: Feb 6, 2004, 5:50 AM
Post ID: 1715967692
John,
100 and 130 psi are not very good numbers for compression - 150 is what
you should be aiming at with less than 10% difference between the
cylinders. To do a compression test there are a few rules to follow:
1. the engine is warmed up to operating temp
2. all spark plugs removed
3. throttle is held wide open for each test
4. wait 'til the maximum psi is obtained
If you get a low reading, pour/squirt in about a tablespoon of oil into
each cylinder and repeat the test. If you get a higher reading, then
the rings are suspect, otherwise the valves are the culprits.
Now, are you sure that when you adjusted the valves, that the piston
was Top Dead Center on the compression stroke? Makes a big difference
on compression tests - and they tend to make more tappet noise.
Bruce
'72 Eldo
John Sutton wrote:
Several weeks ago I asked about points, valves and carbs along with several other things and received great advice. I have adjusted everything to spec and realize that my fuel flow sucks so petcocks are next. I got a compression check done and one cylinder is 100 while the other is 130. What does this mean and what must I do? John S. Eldo |